The real event that changed America into a nation actively at war was the attack on Pearl Harbor. This was precipitated in July 1939 when Franklin Roosevelt announced that the US would no longer trade items such as gasoline and iron to Japan who needed it for their war with China. In July 1941, the Japanese Axis was created. All Japanese assets were frozen in the US. On December 7, 1941, the Japanese surprised attacked Pearl Harbor killing over 2,000 people and damaging or destroying eight battleships greatly harming the Pacific fleet. America officially entered the war and now had to fight on two fronts: Europe and the Pacific.
